Mining-machine bit



June a, 1924. 1,496,263

N. K. BOWMAN MINING MACHINE BIT Filed Jan. 26 192] Fatented June 3, 19241.

NEWTON K. BOA-N, OF NORTH LAWRENCE, OHIO.

MINING- MACHINE BIT.

Application filed January 26, 1921.

T 0 all whom it may concern:

Be it known that I, NEWTON K. BOWMAN, citizen of the United States, residing at North Lawrence, in the county of Stark and State of Ohio, have invented certain new and useful Improvements. in Mining-Machine Bits, of which the following is a specification.

This invention relates to an improved mining machine bit and has as one of its principal objects to provide a device of this character employing a demountable cuttlng tooth of hardened material and wherein the tooth will be of such construction as to present sharp cutting surfaces to the face of the mlne.

The invention has as a further object to provide a bit which may be readily employed in connection with the customary links of a mining machine chain and wherein the cutting tooth may be removed without difliculty.

And the invention has as a still further object to provide a bit wherein the cutting tooth may be tightly clamped in position and wherein said tooth will be rigidly supported for engagement with the work.

Other and incidental objects will appear hereinafter.

In the drawing:

Figure 1 is a fragmentary plan view showing my improved bit in connection with two of the links of a mining machine chain of conventional construction.

Figure 2 is an enlarged sectional view showing one of the links in detail and illustrating the mounting of the bit thereon, and

Figure 3 is a detail perspective view showing the parts of the bit disassembled.

Referring now more particularly to the drawing, I have, in Figure 1, shown a portion of a conventional mining machine chain at 10 and, as usual, this chain is provided with links 11, the bit of the present invention being particularly designed for use in connection with a link of the type illustrated.

In Figure 2, one of the links is illustrated a in detail and, as will be observed, said link is formed with a recess 12 having an inclined bottom wall 13 and threaded through the front wall of said recess is a set screw 14. Intersecting said recess is an angularly disposed opening 15 through the link. The top wall of this opening is formed by an abutment web 16 prolonged to define a nose over- Serial No. 440,120.

hanging the recess and formed on said web as well as the nose is a series of teeth 17. In carrying the invention into effect, I employ a bit holder or stock 18 which fits freely in the opening 15 of the link and is provided at its upper side with teeth 19 meshing with the teeth 17 of the abutment web 16, the stock being formed with a beveled upper end face 20. Near its outer end, the stock is cut away at its lower side to provide aseat 21 substantially ti-shaped in cross section and having diverging flat side faces while at the inner end of said seat is defined an oblique shoulder 22. Fitting freely in the recess 12 is a wedge 23 having an oblique bottom face 24 seating fiat against the wall 13 of said recess to coact therewith while at its outer side the wedge is provided with a vertical face 25 confronting the inner end of the set screw 14. Formed upon the inner side of the wedge near its upper end is a reentrant or female seat 26 which, like the male seat 21 of the stock, is substantially V-shaped in cross section and is provided with fiat side faces. Below the seat 26 the wedge is provided with an oblique face 27 adapted to seat fiat against the lower side of the stock, mating therewith, and, as will be noted, the face 27 is offset with respect to the seat 26, an oblique shoulder 28 being defined between said seat and face. This shoulder is disposed to abut the shoulder 22 of the stock, mating therewith.

A straight cutting tooth 29 is employed. This cutting tooth is formed of hardened material and is substantially V-shaped in cross section, the tooth having flat diverging sides defining, at the forward side of the tooth, a cutting edge 30 extending from end to end of the tooth. At each end, the tooth is beveled to define a cutting prow terminating in a cutting point 31 and having diverging cutting edges 32. The tooth is formed to fit over t e seat 21 of the stock, the sides of the tooth seating fiat against the side faces of said seat and the apex of the seat abutting the crotch between said sides so that the tooth will thus be rigidly supported from end to end thereof. As will be noted, the seat 26 of the wedge 23 is formed to fit over the tooth, the sides of said seat seating flat against the sides of the tooth. Consequently, as will be seen, when the set screw 14 is turned for advancing the wedge in the direction of the stock, the wedge will operate to firmly bind the tooth between said wedge and the stock. At the same time, the

wedge will. also act to hold the teeth of the stock in engagement with the teeth 17 of the web 16 of the link sothat the stock will be locked against longitudinal movement, the

face 27 of the wedge seating fiat against the lower side of the stock and the shoulder 28 of the wedge seating fiat against the shoulder 22 of the stock. As will be observed, the beveled ends of thetooth 29 are inclined to conform to the inclination of the face 20 and shoulder 22 of the stock so that when the tooth is in position, the beveled end of the tooth disposed upwardly for engagement with the work, will overlie and protect the stock, while the beveled end of the tooth disposed downwardly will abut the shoulder 22 seating fiat thereagainst forsustaining the tooth against downward movement. The tooth will accordingly be supported both as against side strain as well as end thrust. By loosening the set screw 14 slightly so as to release the tension of the wedge upon the tooth, the tooth maybe pulled u wardly and removed. As will be perceive this 0 eration of removin the tooth may be re ily accomplished an particular attention is directed to the fact that be to so remove the tooth it is unnecessary displace the wedge or displace the stock. In a similar manner, the tooth may, of course, also be replaced and after one end of the tooth has become dull, the tooth may be turned end for end.

In use, the cutting point 31 of the exposed prow of the tooth will first enter the work for loosening the coal when the cutting edges 32 of said prow will out through the loosened coal with a shearing action, the cut ting edge leading the cutting edges 32 so that these latter edges will always operate against loosened coal. Accordingly, as has been proven in actual practice, much less power will be required to drive a bit of the present character as compared with an ordinary bit so constructed as to merely gouge into or mash the coal of the face of the mine as the bit is advanced. Furthermore, as the ends of the tooth wear away the presence of the cutting edge 30 will serve to maintain the cutting points 31 of the tooth sharp while wear upon the beveled end faces of the sides of the tooth will also tend to maintain the cutting edges 32 sharp as the tooth wears away. I accordingly provide a tooth of highly eliicient design.

Having thus described the invention, what is claimed as new is:

1. A bit for mining machines including a stock, a wedge binding the stock stationary, and a cutting tooth clamped between the stockand wedge engaged by the wedge.

2. A. bit for mining machines including a stock, a wedge binding the stock stationary, and a cutting tooth clamped between the aeaaoe.

stock and wedge'en a d by. the wed the tooth being provid%d iit one side v v ith a channeled ace.

3. A. bit for mining machines including a stock, a wed e bindlng the stock stationary, and a su stantially V-shaped cutting tooth clam ed between the stock and wedge and provided with beveled ends.

4. A bit for mining machines including a stock, a wedge binding the stock stationy, clamped between the stock and wedge and provided with beveled ends, the tooth being reversible end for end upon the stock.

5. A bit for mining machines including a stock, a wedge coacting therewith, and

and a double-ended cutting tooth.

a substantially ll-shaped cutting tooth clamped between the stock and wedge and provided with beveled ends, the stock being provided with an inclined shoulder and one end of the tooth abutting said shoulder.

6. A bit for mining machines including a stock having a substantially V-shaped seat a wedge binding the stock station'a an provided 'with a substantially V- s liaped seat, and a substantially V-shaped cuttmg tooth fitting said seats and clamped theretween.

7. A bit for mining machines including a stock having a seat and formed at the inner end of said seat with an inclined shoulder, a wedge coacting with the stock and formed wit an inclined face to abut said shoulder, and a cutting tooth clamped between the wedge and said seat resting at one end against the shoulder.

8. The combination with a mining machine chain link having a recess and further provided with an opening having a wall thereof provided with teeth, of a stock disposed in said opening and provided with teeth to coact with said first mentioned teeth, a wedge disposed in said recess to coact with the stock, and a cutting tooth clamped between the wedges and stock.

9. The combination with a mining machine chain link having a recess intersected by an opening, the recess being formed with an inclined bottom wall and a wall of the opening being provided with teeth, and a set screwadjustable upon the link to project into said recess, of a stock disposed in said opening and provided with teeth to coact with said first mentioned teeth, a wedge disposed in said recess to coact with t e stock and engageable by said set screw, the wedge being provided with an inclined face to coact with the bottom wall of said recess, and a cutting tooth disposed between the stock and wedge, the set screw being adjustable to advance the wedge for binding the teeth of the stock in engagement with said first mentioned teeth and clamping the cutting tooth between the wedge and stock.

.10. The combination with a mining memenses chine chain link, of a stock mounted upon the link, a Wedge binding the stock in engagement With the link, and a cutting tooth clamped between the Wedge and stock.

11. As a new article of manufacture, a double-ended reversible mining machine cutting tooth straight from end to end and having angulerly disposed sides, the ends of the tooth being beveled and the beveled ends thereof converging in the direction of 1 the free edges of said. sides to define terminal cutting points at the plane of the junction between the sides.

In testimony whereof I aflix my signature.

NEWTON K. BOWMAN. [1,. s.] 

